Medina Velecela, Ricardo David; Romero Quete, Andres Arturo; Esteban Mombello, Enrique; Ratta, Giuseppe; Morales Jadan, Diego Xavier: 'Assessing DP value of a power transformer considering thermal ageing and paper moisture' (Energy Engineering, 2018), 'Power Transformer Condition Monitoring and Diagnosis', Chap. 4, pp. 125-142, DOI: 10.1049/PBPO104E_ch4
IET Digital Library, https://digital-library.theiet.org/;jsessionid=bew7ogff6qmr.x-iet-live-01content/books/10.1049/pbpo104e_ch4